<?php

/**
 * @file
 * Advanced CSS/JS aggregation module.
 */

use Drupal\Core\Url;
use Drupal\Component\Utility\Crypt;

// Core hook implementations.
/**
 * Implements hook_hook_info().
 */
function advagg_hook_info() {
  // List of hooks that should be inside of *.advagg.inc files.
  // All advagg hooks except for:
  // advagg_current_hooks_hash_array_alter
  // advagg_hooks_implemented_alter
  // because these 3 hooks are used on most requests.
  $advagg_hooks = [
    'advagg_aggregate_grouping_alter',
    'advagg_css_contents_alter',
    'advagg_js_contents_alter',
    'advagg_scan_file_alter',
  ];
  $hooks = [];
  foreach ($advagg_hooks as $hook) {
    $hooks[$hook] = ['group' => 'advagg'];
  }
  return $hooks;
}

/**
 * Implements hook_module_implements_alter().
 *
 * Move advagg' and various submodule's implementations to last.
 */
function advagg_module_implements_alter(&$implementations, $hook) {
  if ($hook === 'js_alter' && isset($implementations['advagg'])) {
    // Move advagg and advagg_mod to the bottom, advagg is above advagg_mod.
    $item = $implementations['advagg'];
    unset($implementations['advagg']);
    $implementations['advagg'] = $item;
    if (isset($implementations['advagg_mod'])) {
      $item = $implementations['advagg_mod'];
      unset($implementations['advagg_mod']);
      $implementations['advagg_mod'] = $item;
    }
  }
  elseif ($hook === 'css_alter' && isset($implementations['advagg'])) {
    $item = $implementations['advagg'];
    unset($implementations['advagg']);
    $implementations['advagg'] = $item;
    if (isset($implementations['advagg_mod'])) {
      $item = $implementations['advagg_mod'];
      unset($implementations['advagg_mod']);
      $implementations['advagg_mod'] = $item;
    }
  }
  if ($hook === 'file_url_alter' && isset($implementations['advagg'])) {
    $item = $implementations['advagg'];
    unset($implementations['advagg']);
    $implementations['advagg'] = $item;
  }
  if ($hook === 'requirements') {
    if (isset($implementations['advagg'])) {
      $item = $implementations['advagg'];
      unset($implementations['advagg']);
      $implementations['advagg'] = $item;
    }
    if (isset($implementations['advagg_cdn'])) {
      $item = $implementations['advagg_cdn'];
      unset($implementations['advagg_cdn']);
      $implementations['advagg_cdn'] = $item;
    }
    if (isset($implementations['advagg_css_minify'])) {
      $item = $implementations['advagg_css_minify'];
      unset($implementations['advagg_css_minify']);
      $implementations['advagg_css_minify'] = $item;
    }
    if (isset($implementations['advagg_js_minify'])) {
      $item = $implementations['advagg_js_minify'];
      unset($implementations['advagg_js_minify']);
      $implementations['advagg_js_minify'] = $item;
    }
  }
}

/**
 * Implements hook_cron().
 *
 * This will be ran once a day at most.
 *
 * @param bool $bypass_time_check
 *   Set to TRUE to skip the 24 hour check.
 */
function advagg_cron($bypass_time_check = FALSE) {
  $state = \Drupal::state();
  // Execute once a day (24 hours).
  if (!$bypass_time_check && $state->get('advagg.cron_timestamp', REQUEST_TIME) > (REQUEST_TIME - \Drupal::config('advagg.settings')->get('cron_frequency'))) {
    return [];
  }
  $state->set('advagg.cron_timestamp', REQUEST_TIME);

  $return = [];
  $return['stale'] = [
    'js' => \Drupal::service('asset.js.collection_optimizer')->deleteStale(),
    'css' => \Drupal::service('asset.css.collection_optimizer')->deleteStale(),
  ];

  return $return;
}

/**
 * Implements hook_js_alter().
 */
function advagg_js_alter(&$js) {
  // Skip if advagg is disabled.
  if (!advagg_enabled()) {
    return;
  }

  // Add DNS information for some of the more popular modules.
  foreach ($js as &$value) {
    if (!is_string($value['data'])) {
      continue;
    }
    // Google Ad Manager.
    if (strpos($value['data'], '/google_service.') !== FALSE) {
      if (!empty($value['dns_prefetch']) && is_string($value['dns_prefetch'])) {
        $temp = $value['dns_prefetch'];
        unset($value['dns_prefetch']);
        $value['dns_prefetch'] = [$temp];
      }
      // Domains in the google_service.js file.
      $value['dns_prefetch'][] = 'https://csi.gstatic.com';
      $value['dns_prefetch'][] = 'https://pubads.g.doubleclick.net';
      $value['dns_prefetch'][] = 'https://partner.googleadservices.com';
      $value['dns_prefetch'][] = 'https://securepubads.g.doubleclick.net';

      // Domains in the google_ads.js file.
      $value['dns_prefetch'][] = 'https://pagead2.googlesyndication.com';

      // Other domains that usually get hit.
      $value['dns_prefetch'][] = 'https://cm.g.doubleclick.net';
      $value['dns_prefetch'][] = 'https://tpc.googlesyndication.com';
    }

    // Google Analytics.
    if (strpos($value['data'], 'GoogleAnalyticsObject') !== FALSE
      || strpos($value['data'], '.google-analytics.com/ga.js') !== FALSE
    ) {
      if (!empty($value['dns_prefetch']) && is_string($value['dns_prefetch'])) {
        $temp = $value['dns_prefetch'];
        unset($value['dns_prefetch']);
        $value['dns_prefetch'] = [$temp];
      }
      if (strpos($value['data'], '.google-analytics.com/ga.js') !== FALSE) {
        $value['dns_prefetch'][] = 'https://ssl.google-analytics.com';
      }
      $value['dns_prefetch'][] = 'https://stats.g.doubleclick.net';
    }
  }
  unset($value);

  // Fix type if it was incorrectly set.
  if (\Drupal::config('advagg.settings')->get('js_fix_type')) {
    // Get hostname and base path.
    $mod_base_url = substr($GLOBALS['base_root'] . $GLOBALS['base_path'], strpos($GLOBALS['base_root'] . $GLOBALS['base_path'], '//') + 2);
    $mod_base_url_len = strlen($mod_base_url);

    foreach ($js as &$value) {
      // Skip if the data is empty or not a string.
      if (empty($value['data']) || !is_string($value['data'])) {
        continue;
      }

      // Default to file if not file or external.
      if ($value['type'] !== 'file' && $value['type'] !== 'external') {
        if ($value['type'] === 'settings') {
          $value['type'] = 'setting';
        }
        else {
          $value['type'] = 'file';
        }
      }

      // If type is external but doesn't start with http, https, or // change it
      // to file.
      if ($value['type'] === 'external'
        && stripos($value['data'], 'http://') !== 0
        && stripos($value['data'], 'https://') !== 0
        && stripos($value['data'], '//') !== 0
        ) {
        $value['type'] = 'file';
      }

      // If type is file but it starts with http, https, or // change it to
      // external.
      if ($value['type'] === 'file'
        && (stripos($value['data'], 'http://') === 0
        || stripos($value['data'], 'https://') === 0
        || (stripos($value['data'], '//') === 0 && stripos($value['data'], '///') === FALSE))
        ) {
        $value['type'] = 'external';
      }

      // If type is external and starts with http, https, or // but points to
      // this host change to file, but move it to the top of the aggregation
      // stack as long as js_preserve_external is not set.
      if (\Drupal::config('advagg.settings')->get('js_preserve_external') === FALSE) {
        if ($value['type'] === 'external'
          && stripos($value['data'], $mod_base_url) !== FALSE
          && (stripos($value['data'], 'http://') === 0
            || stripos($value['data'], 'https://') === 0
            || stripos($value['data'], '//') === 0
          )
        ) {
          $value['type'] = 'file';
          $value['group'] = JS_LIBRARY;
          $value['every_page'] = TRUE;
          $value['weight'] = -40000;
          $value['data'] = substr($value['data'], stripos($value['data'], $mod_base_url) + $mod_base_url_len);
        }
      }
    }
    unset($value);
  }
}

/**
 * Implements hook_css_alter().
 */
function advagg_css_alter(&$css) {
  if (!advagg_enabled()) {
    return;
  }
  if (\Drupal::config('advagg.settings')->get('css.fix_type')) {
    // Fix type if it was incorrectly set.
    foreach ($css as &$value) {
      if (empty($value['data']) || !is_string($value['data'])) {
        continue;
      }

      // Default to file if not set.
      if ($value['type'] !== 'file' && $value['type'] !== 'external') {
        $value['type'] = 'file';
      }

      // If type is external but doesn't start with http, https, or // change it
      // to file.
      if ($value['type'] === 'external'
        && stripos($value['data'], 'http://') !== 0
        && stripos($value['data'], 'https://') !== 0
        && stripos($value['data'], '//') !== 0
        ) {
        $value['type'] = 'file';
      }

      // If type is file but it starts with http, https, or // change it to
      // external.
      if ($value['type'] === 'file'
        && (stripos($value['data'], 'http://') === 0
        || stripos($value['data'], 'https://') === 0
        || (stripos($value['data'], '//') === 0
        && stripos($value['data'], '///') === FALSE
        )
        )
      ) {
        $value['type'] = 'external';
      }
    }
    unset($value);
  }
}

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * Give advice on how to temporarily disable css/js aggregation.
 */
function advagg_form_system_performance_settings_alter(&$form, &$form_state) {
  $msg = t('NOTE: If you wish to bypass aggregation for a set amount of time, you can go to the <a href="@operations">AdvAgg operations</a> page and press the "aggregation bypass cookie" button.', [
    '@operations' => Url::fromRoute('advagg.operations')->toString(),
  ]);

  if (\Drupal::currentUser()->hasPermission('bypass advanced aggregation')) {
    $msg .= t('You can also selectively bypass aggregation by adding <code>@code</code> to the URL of any page.', [
      '@code' => '?advagg=0',
    ]);
  }
  else {
    $msg .= t('You do not have the <a href="@permission">bypass advanced aggregation permission</a> so adding <code>@code</code> to the URL will not work at this time for you; either grant this permission to your user role or use the bypass cookie if you wish to selectively bypass aggregation.', [
      '@permission' => Url::fromRoute('user.admin_permissions')->toString(),
      '@code' => '?advagg=0',
    ]);
  }

  $form['bandwidth_optimization']['advagg_note'] = [
    '#markup' => $msg,
  ];
}

/**
 * Returns TRUE if the CSS is being loaded via JavaScript.
 *
 * @return bool
 *   TRUE if CSS loaded via JS. FALSE if not.
 */
function advagg_css_in_js() {
  if (\Drupal::moduleHandler()->moduleExists('advagg_mod')
      && \Drupal::config('advagg_mod.settings')->get('css_defer')
    ) {
    return TRUE;
  }
  return \Drupal::config('advagg.settings')->get('advagg_css_in_js');
}

// Helper functions.
/**
 * Function used to see if aggregation is enabled.
 *
 * @return bool
 *   The value of the advagg_enabled variable.
 */
function advagg_enabled() {
  $init = &drupal_static(__FUNCTION__);

  if (!empty($init)) {
    return $init['advagg'];
  }

  $advagg_config = \Drupal::config('advagg.settings');
  $user = \Drupal::currentUser();
  $init['advagg'] = $advagg_config->get('enabled');

  // Disable AdvAgg if maintenance mode is defined.
  if (defined('MAINTENANCE_MODE')) {
    $init['advagg'] = FALSE;
    return FALSE;
  }
  // Allow for AdvAgg to be enabled/disabled per request.
  if (isset($_GET['advagg']) && $user->hasPermission('bypass advanced aggregation')) {
    if ($_GET['advagg'] == 1) {
      $init['advagg'] = TRUE;
    }
    else {
      $init['advagg'] = FALSE;
    }
  }

  // Do not use AdvAgg if the disable cookie is set.
  $cookie_name = 'AdvAggDisabled';
  $key = Crypt::hashBase64(\Drupal::service('private_key')->get());
  if (!empty($_COOKIE[$cookie_name]) && $_COOKIE[$cookie_name] == $key) {
    $init['advagg'] = FALSE;

    // Let the user know that the AdvAgg bypass cookie is currently set.
    static $msg_set;
    if (!isset($msg_set) && $advagg_config->get('show_bypass_cookie_message')) {
      $msg_set = TRUE;
      if (\Drupal::currentUser()->hasPermission('administer site configuration')) {
        drupal_set_message(t('The AdvAgg bypass cookie is currently enabled. Turn it off by going to the <a href="@advagg_operations">AdvAgg Operations</a> page and clicking the <em>Toggle the "aggregation bypass cookie" for this browser</em> button.', [
          '@advagg_operations' => Url::fromRoute('advagg.operations', [], ['fragment' => 'edit-bypass'])->toString(),
        ]));
      }
      else {
        drupal_set_message(t('The AdvAgg bypass cookie is currently enabled. Turn it off by <a href="@login">logging in</a> with a user with the "administer site configuration" permissions and going to the AdvAgg Operations page (located at @advagg_operations) and clicking the <em>Toggle the "aggregation bypass cookie" for this browser</em> button.', [
          '@login' => '/user/login',
          '@advagg_operations' => Url::fromRoute('advagg.operations')->toString(),
        ]));
      }
    }
  }

  // Enable debugging if requested.
  if (isset($_GET['advagg-debug'])
    && $_GET['advagg-debug'] == 1
    && $user->hasPermission('bypass advanced aggregation')
    ) {
    global $config;
    $config['advagg.settings']['debug'] = TRUE;
  }

  return $init['advagg'];
}

/**
 * Get an array of all hooks and settings that affect aggregated files contents.
 *
 * @return array
 *   ['variables' => [], 'hooks' => []]
 */
function advagg_current_hooks_hash_array() {
  $aggregate_settings = &drupal_static(__FUNCTION__);
  if (isset($aggregate_settings)) {
    return $aggregate_settings;
  }

  $config = \Drupal::config('advagg.settings');

  // Put all enabled hooks and settings into a big array.
  $aggregate_settings = [
    'variables' => ['advagg' => $config->get()],
    'hooks' => advagg_hooks_implemented(FALSE),
  ];

  // Add in language if locale is enabled.
  if (\Drupal::moduleHandler()->moduleExists('locale')) {
    $aggregate_settings['variables']['language'] = isset(\Drupal::languageManager()->getCurrentLanguage()->language) ? \Drupal::languageManager()->getCurrentLanguage()->language : '';
  }

  // Add the base url if so desired to.
  if ($config->get('include_base_url')) {
    $aggregate_settings['variables']['base_url'] = $GLOBALS['base_url'];
  }

  // Allow other modules to add in their own settings and hooks.
  // Call hook_advagg_current_hooks_hash_array_alter().
  \Drupal::moduleHandler()->alter('advagg_current_hooks_hash_array', $aggregate_settings);

  return $aggregate_settings;
}

/**
 * Get the serialization function.
 *
 * @return string
 *   The serializer. Defaults to json_encode.
 */
function advagg_get_serializer() {
  $serialize_function = \Drupal::config('advagg.settings')->get('serializer');
  if (!is_string($serialize_function) || !is_callable($serialize_function)) {
    $serialize_function = 'json_encode';
  }
  return $serialize_function;
}

/**
 * Get the hash of all hooks and settings that affect aggregated files contents.
 *
 * @return string
 *   hash value.
 */
function advagg_get_current_hooks_hash() {
  $current_hash = &drupal_static(__FUNCTION__);

  if (!isset($current_hash)) {
    // Get all advagg hooks and variables in use.
    $aggregate_settings = advagg_current_hooks_hash_array();

    // Generate the hash.
    $serialize_function = advagg_get_serializer();
    $current_hash = Crypt::hashBase64($serialize_function($aggregate_settings));
  }

  return $current_hash;
}

/**
 * Get back what hooks are implemented.
 *
 * @param bool $all
 *   If TRUE get all hooks related to css/js files.
 *   if FALSE get only the subset of hooks that alter the filename/contents.
 *
 * @return array
 *   List of hooks and what modules have implemented them.
 */
function advagg_hooks_implemented($all = TRUE) {
  $hooks = &drupal_static(__FUNCTION__);
  if ($hooks) {
    return $hooks;
  }
  $module_handler = \Drupal::moduleHandler();

  // Get hooks in use.
  $hooks = [
    'advagg_aggregate_grouping_alter' => [],
    'advagg_css_contents_alter' => [],
    'advagg_js_contents_alter' => [],
    'advagg_current_hooks_hash_array_alter' => [],
    'advagg_hooks_implemented' => [],
  ];
  if ($all) {
    $hooks += [
      'js_alter' => [],
      'css_alter' => [],
    ];
  }
  // Call hook_advagg_hooks_implemented_alter().
  $module_handler->alter('advagg_hooks_implemented', $hooks, $all);

  // Cache module_implements as this will load up .inc files.
  $serialize_function = advagg_get_serializer();
  $cid = 'advagg_hooks_implemented:' . (int) $all . ':' . Crypt::hashBase64($serialize_function($hooks));
  $cache = \Drupal::cache('bootstrap')->get($cid);
  if (!empty($cache->data)) {
    $hooks = $cache->data;
  }
  else {
    foreach ($hooks as $hook => $values) {
      $hooks[$hook] = $module_handler->getImplementations($hook);

      // Also check themes as drupal_alter() allows for themes to alter things.
      $theme_keys = \Drupal::service('theme_handler')->listInfo();
      if (!empty($theme_keys)) {
        foreach ($theme_keys as $theme_key => $info) {
          $function = $theme_key . '_' . $hook;
          if (function_exists($function)) {
            $hooks[$hook][] = $info['name'];
          }
        }
      }
    }
    \Drupal::cache('bootstrap')->set($cid, $hooks, REQUEST_TIME + 600);
  }
  return $hooks;
}

/**
 * Given a uri, get the relative_path.
 *
 * @param string $uri
 *   The uri for the stream wrapper.
 *
 * @return string
 *   The relative path of the uri.
 *
 * @see https://www.drupal.org/node/837794#comment-9124435
 */
function advagg_get_relative_path($uri) {
  $wrapper = \Drupal::service("stream_wrapper_manager")->getViaUri($uri);
  if ($wrapper instanceof DrupalLocalStreamWrapper) {
    $relative_path = $wrapper->getDirectoryPath() . '/' . file_uri_target($uri);
  }
  else {
    $relative_path = parse_url(file_create_url($uri), PHP_URL_PATH);
    if (substr($relative_path, 0, strlen($GLOBALS['base_path'])) == $GLOBALS['base_path']) {
      $relative_path = substr($relative_path, strlen($GLOBALS['base_path']));
    }
  }
  return $relative_path;
}

/**
 * Return the global_counter variable.
 *
 * @return int
 *   Int value.
 */
function advagg_get_global_counter() {
  $counter = &drupal_static(__FUNCTION__);
  if (!$counter) {
    $counter = \Drupal::config('advagg.settings')->get('global_counter');
    if ($counter === NULL) {
      $counter = 0;
    }
  }
  return $counter;
}

/**
 * Stable sort for CSS and JS items.
 *
 * Preserves the order of items with equal sort criteria.
 *
 * The function will sort by:
 * - $item['group'],      integer, ascending
 * - $item['weight'],     integer, ascending
 *
 * @param array &$items
 *   Array of JS or CSS items, as in hook_alter_js() and hook_alter_css().
 *   The array keys can be integers or strings. The items themselves are arrays.
 *
 * @see hook_alter_js()
 * @see hook_alter_css()
 */
function advagg_drupal_sort_css_js_stable(array &$items) {
  $nested = [];
  foreach ($items as $key => $item) {
    // Weight cast to string to preserve float.
    $weight = (string) $item['weight'];
    $nested[$item['group']][$weight][$key] = $item;
  }
  // First order by group, so that, for example, all items in the CSS_SYSTEM
  // group appear before items in the CSS_DEFAULT group, which appear before
  // all items in the CSS_THEME group. Modules may create additional groups by
  // defining their own constants.
  $sorted = [];
  // Sort group; then iterate over it.
  ksort($nested);
  foreach ($nested as &$group_items) {
    // Order by weight and iterate over it.
    ksort($group_items);
    foreach ($group_items as &$weight_items) {
      foreach ($weight_items as $key => &$item) {
        $sorted[$key] = $item;
      }
      unset($item);
    }
    unset($weight_items);
  }
  unset($group_items);
  $items = $sorted;
}

/**
 * Converts absolute paths to be self references.
 *
 * @param string $path
 *   Path to check.
 *
 * @return string
 *   The path.
 */
function advagg_convert_abs_to_rel($path) {
  if (strpos($path, $GLOBALS['base_url']) === 0) {
    $base_url = $GLOBALS['base_url'];
    // Add a slash if none is found.
    if (stripos(strrev($base_url), '/') !== 0) {
      $base_url .= '/';
    }
    $path = str_replace($base_url, $GLOBALS['base_path'], $path);
  }
  return $path;
}

/**
 * Converts absolute paths to be protocol relative paths.
 *
 * @param string $path
 *   Path to check.
 *
 * @return string
 *   The path.
 */
function advagg_path_convert_protocol_relative($path) {
  if (strpos($path, 'https://') === 0) {
    $path = substr($path, 6);
  }
  elseif (strpos($path, 'http://') === 0) {
    $path = substr($path, 5);
  }
  return $path;
}

/**
 * Convert http:// to https://.
 *
 * @param string $path
 *   Path to check.
 *
 * @return string
 *   The path.
 */
function advagg_path_convert_force_https($path) {
  if (strpos($path, 'http://') === 0) {
    $path = 'https://' . substr($path, 7);
  }
  return $path;
}

/**
 * Convert the saved advagg cache level to a time interval.
 *
 * @param int $level
 *   The cache level.
 *
 * @return int
 *   The time interval.
 */
function advagg_get_cache_time($level = 0) {
  switch ($level) {
    case 1:
    case 3:
      return 86400;

    case 5:
      return 604800;

    case 0:
    default:
      return 0;
  }
}